From 64c60582b54e6b8b25bb94835bf5ee17469ef5ca Mon Sep 17 00:00:00 2001
From: Ian Romanick <ian.d.romanick@intel.com>
Date: Sat, 7 Mar 2026 11:26:44 -0800
Subject: [PATCH] elk/algebraic: Don't optimize SEL.L.SAT or SEL.G.SAT

shader-db:

Broadwell
total instructions in shared programs: 18607516 -> 18607530 (<.01%)
instructions in affected programs: 2095 -> 2109 (0.67%)
helped: 0 / HURT: 8

total cycles in shared programs: 955704436 -> 955702925 (<.01%)
cycles in affected programs: 34299 -> 32788 (-4.41%)
helped: 2 / HURT: 6

All Haswell and older platforms had similar results. (Haswell shown)
total instructions in shared programs: 16989200 -> 16989201 (<.01%)
instructions in affected programs: 461 -> 462 (0.22%)
helped: 0 / HURT: 1

total cycles in shared programs: 946537070 -> 946537035 (<.01%)
cycles in affected programs: 16378 -> 16343 (-0.21%)
helped: 1 / HURT: 0

Test: piglit!1100
Reported-by: Georg Lehmann
Fixes: ca675b73d3a ("i965/fs: Optimize saturating SEL.L(E) with imm val >= 1.0.")
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/40284>
---
 src/intel/compiler/elk/elk_fs.cpp | 37 -------------------------------
 1 file changed, 37 deletions(-)

diff --git a/src/intel/compiler/elk/elk_fs.cpp b/src/intel/compiler/elk/elk_fs.cpp
index 6483bb2b6f5..ead4475bc61 100644
--- a/src/intel/compiler/elk/elk_fs.cpp
+++ b/src/intel/compiler/elk/elk_fs.cpp
@@ -2367,43 +2367,6 @@ elk_fs_visitor::opt_algebraic()
             inst->predicate_inverse = false;
             inst->conditional_mod = ELK_CONDITIONAL_NONE;
             progress = true;
-         } else if (inst->saturate && inst->src[1].file == IMM) {
-            switch (inst->conditional_mod) {
-            case ELK_CONDITIONAL_LE:
-            case ELK_CONDITIONAL_L:
-               switch (inst->src[1].type) {
-               case ELK_REGISTER_TYPE_F:
-                  if (inst->src[1].f >= 1.0f) {
-                     inst->opcode = ELK_OPCODE_MOV;
-                     inst->sources = 1;
-                     inst->src[1] = reg_undef;
-                     inst->conditional_mod = ELK_CONDITIONAL_NONE;
-                     progress = true;
-                  }
-                  break;
-               default:
-                  break;
-               }
-               break;
-            case ELK_CONDITIONAL_GE:
-            case ELK_CONDITIONAL_G:
-               switch (inst->src[1].type) {
-               case ELK_REGISTER_TYPE_F:
-                  if (inst->src[1].f <= 0.0f) {
-                     inst->opcode = ELK_OPCODE_MOV;
-                     inst->sources = 1;
-                     inst->src[1] = reg_undef;
-                     inst->conditional_mod = ELK_CONDITIONAL_NONE;
-                     progress = true;
-                  }
-                  break;
-               default:
-                  break;
-               }
-               break;
-            default:
-               break;
-            }
          }
          break;
       case ELK_OPCODE_MAD: